Gas making apparatus



Dec. 5, 1933. H 0' LOEBELL GAS MAKING APPARATUS Original Filed May 23,1923 2 Sheets-Sheet 1 BY g a INVENTOR: HENRY O. LOEBELL ATTORNEY Dec. 5,1933. H O LOEBELL 1,937,580

GAS MAKING APPARATUS Original Filed May 23', 1923 2 Sheets-Sheet 2INVENTOR HENRY O. LOEBELL BY 2 ATTORNEY l atented Dec. 5,;

1,937,580 GAS MAKING APPARATUs 1 Henry 0 Loebell, Malba, N. Y.,.assignorto p .HenryL. Doherty, New York, N. Y.

Original application May 23, 1923, "Serial No.

640,828. Divided and this application May"23,-

making gas for industr 1931. January 31, 1924 Serial No. 539,600, and inGreatBritain '1 Claims. (01. 202- 88) This invention relates to themanufacture of fuel gas, and more particularly to a method of ialpurposes by the complete gasiflcation of coal. r

The gas which is now being commonly burned for industrial heatingpurposes is known as a producer gas which has a comparatively lowcalorific value. This gas is manufactured by a process of burning coalwherein inert materials such as nitrogen of the air used and carbondioxide formed by combustion of carbon with the air remain in the gas sothat to %of the gas is inert material; Producer gas has a limited usefor industrial heating purposes, because it has a low flame temperature,

a low calorific value and a slow flame propagation. Some heatingprocesses require comparati tures and an attempt a blue water gas forthis purpose.

vely high flame temperahas been made to make The so called blue gas hasa comparatively high flametemperature and a compar inert materials, butthe Water gas is'very high water gas from a'ton small as compared withthe amount of producer gas which can be made One object of the presentinvention is to pro vide a method of manufacturing an industrial ativelylow percentage of cost to manufacture blue and the yield of the blue ofcoal is comparatively from atom of coal.

fuel gas which has a comparatively high flame temperature, a rapid flamepropagation, and a calorific value which'adapts it for practically allindustrial heating purposes.

Another object of th a method of making e invention is to provideindustrial gas by which of gas being made.

' With these and other view, the invention con sists the improved' g'asmaking process hereinafter described and specifically defined in theclaims.

The various features of the invention are illustrated in the whichccompanying drawings, in

Fig. 1 is a viewin vertical section with parts in elevation of a gasgenerator embodying the preferred form of the 'Fig. 2 is a top plan viewof the generator shownin'Fig. 1; I Fig. 3 is a vertical se inventionctional view of the waste generator; and

orator shaft.

objects .and featuresin' heat boiler used with the generator, thesection I being'taken on the line 3,3 (if-Fig. 2; p

Fig. 4 is a horizontal sectional view :taken on the line 4-4 of Fig; 5,illustrating-"the mechanism for removing coke'from the bottom of the 30Fig. 5 is a vertical sectional viewtaken onthe line 55 of Fig. 4 toillustrate the coke' discharging mechanism. The method of making fuelgas embodying the preferred form of the invention maybe carried out inthe apparatus illustrated in the' drawings substantially as follows:Fuel to be carbonized, which is preferably a coking grade of bituminouscoal in mixture with coke,-is-p1aced in a hopper 10 and isintermittently introduced into the upperpart of a generator-shaft 12by'means of a pocket 14 and intermittently operated valves 16 and 18.When the valve 16 is moved downwardly,

the pocket 14 will be filled with'coal. At this 2 time the valve 18 isclosed. Thereupon the valve 16 will be closed and the valvelS will beopened to allow the fuel to pass into the top of the gen- The fueldischarging from the pocket 14; passes around a central'gas off-take 20and is distributed into the top of an upright column of fuel supportedinthe shaft 12.- The upper portion of the fuel column or approximately theportion above the lower end of the gas offtake 20, comprises a coalcarbonizing zone." The 35 portion of the fuel column below'the bottom ofthe off-take 20- and extending downwardly a short distance below anoffset portion 22 in the shaft 12 constitutes a blast zone in which thefuel is maintained at a comparatively high temperature by partialcombustionthereof. 1 The portion of the fuel columnfro'm the bottom ofthe blast zone to the bottom of the column is a cooling or quenchingzone in which the unburned carbonized fuel and ashes are quenched beforebeing removed from the generator. The unburned carbonized fuel iscontinuously dis;

'ch'arged from the bottom of the column and con- 7 tinuously movesdownwardly through the shaft.

' The gas is made'byseveral' distinct reactions whichtake place betweenthe fuel'and the air .and steam used for making the gas. The firstreaction is an'eXOtheImic reaction which takes place when-air is usedto-burn carbon of the 1 5 of the fuel bed and. the'carbon dioxide whichis Y' at aitime.

.is mounted inthe'inletfiue 4a in a position to bottom of the centralofif-take 20.

formed by the combustion of air, in accordance with the followingequation, which is endo thermic:

C+CO2=2CO-5900 B. t. u.

A third reactiontakes place between carbon of 'the fuel bed and steamwhich is introduced at the fuel bed, the reaction being endothermic, as

follows:

A fourth reaction is that which takes place'when air and steam is heatedin a pair of.preheaterswhich are so arranged that one preheater is usedfor preheating the mixture, while the other preheater is being heated byburning gas therein. When one preheaterhas been cooled to the minimumworking temperature which is desirable,- by

passing steam and air through it, the circulation of the steam and airmixture is stopped and then started in the-other preheater which wasbeing heated; during the time when the first preheater was used forheating the mixture of steam and air. To accomplish this air isintroduced into one of the preheaters VZ lthrough a pipe 26, and steamis supplied to, the pipe 26 through a pipe 28. Thesteamand air mixtureenters the top of an exhaust section 30 of the preheater, passesdownwardly through a checker brick filling in the sectionf30, thenthrough an opening 32 into the bottom of the main section of thepreheater 24,

randthencepasses upwardly through a checker brick fillingin the mainsection, In passing through the two sections of the preheater the steam,and air mixture becomes highly heated and it then flows through a blastneck 34 into a passage 36 surrounding the blast portion of the fuelcolumn; From the passage 36 the mixture of steamand air enters the fuelcolumn, a portion of; it'forcin'g its way through the column to the Inpassing through the fuel column the fuelgas'is made principally by thefirst three reactions outlined ,above, andthe hot gas formed passes:upwardly through the off-take in contact with a series of superheatingtubes 38, wherein water, vapor or steam to be used forthe gas makingoperation is superheated before it is introduced through the.pipes'28'into sections 30 of preheaters24. After passing through theoff-take 20 the gasflows "throughoutlets 40, Figs. 1 and 2, to a conduit42 which conducts it to, inlet flues 44 of waste heat boilers 46 and 8.In the waste heat boilers the hot. gaspasses upwardly through a seriesof tubes 50, Fig. 3, to a passage 52 at the top of ,the boiler, thendownwardly through tubes 54 to an outlet fine 56, whence the gaspassesthrough a conduit58 to a cooler of suitable construction, whereby thegas may be cooled and be 'ready 'to pass to the place of consumptionorto the usual holder (not shown).

In normal operation of the gas generator the hot-'g'as carriedoif'through the off-take 20 is used to' heat the boilers 46 and 48simultaneously.

If, however, one of the boilers needs to be cleaned or. if one of theboilersgets'out of-order, all of the gas may be passed through one ofthe boilers Io-accomplish this a valve 60, Fig. 1,

which are usually formed in coal gas.

be moved into a valve seat 62 positioned at the bottom of the conduit42. The valve is mountthe left of Fig. 1, is used for preheating the airand steam mixture, the preheater 24, shown at the right, is being heatedby burning gas therein. At thistirne the preheater 24 at the right ofFig.

1 is cut off from the shaft 12 by means of a valve '76, and a portion ofthe gas from the conduit 58 is conducted through a pipe 78 and valve80-into the top of the main section of the preheater. At the same timeair is introduced through an inlet 82, and the mixture'of burning gasand air passes downwardly through the main section of the preheater,thenaupwardly through the exhaust section 30 of the preheater, and;exhausts through an outlet 84.. A cover '86. on the outlet-84 is openduring the heating operationof the preheater, and the air and steaminlet pipes 26 and 28are closed respectively by suitable valves 85 and87. (Fig. 1) y The central off-take 20. which functions as a heatexchange means is supported on the top' of the shaft '12 by the outletpipes 40*andalso by a series of braces 88 which are attached to theframe 90 of the generator. the off-take consists of the superheatingtubes 38 which are connected between an inlet manifold 92 at the top,Figs. 1 and 2, a distributing manifold 94 at the bottom, and an outletmanifold 96 at the top. The steam to be superheated, is introduced intothe inlet manifold 92v by-means of a pipe which connects with a steamheader 9'2, mounted between the waste heat boilers 46 and i8. Suitablevalves 98 and 100are placed in the header 97 to control the flow ofsteam from the boilers. The steam flows fromthe inlet header 92downwardly through tubes 38 to the header 9 irand then upwardly throughtubes to the header 96 and out through a pipe 102, which preferably isconnected with the sections 30' of the preheaters 24; Water .isintroduced into the waste heat boilers through inlet pipesil04. Thewaste heat. boilers will abstract the larger portion of the heat fromthe fuel gas and this heat will normally produce a sufficient amount, ofsteam to take care of the requirements'of the gas making operation.I-Iowever,- the wasteheat boilers may be. supplemented with other steamboilers in makingup the required amount of steam, so that onset theWaste heat boilers may be shut down-for any desired purpose.

By the time the fuel has moved downwardly throughthe'carbonizing zoneand reached the blast zone there is substantially no volatilemae Theinner. lining of terial therein and therefore the gas which passesupwardly, through the offtake 20 contains. substantially no tar,ammonia, or other products Accordingly, the gas which leaves the wasteheat .boilers does not require any special purification.

' The volatile material of the coal and other valuable icy-products suchas tars, oils andammoniaare removed from the coal by low tem- This smallamount of gascontaining the byproducts' passes into a peripheral outlet106-at the top of the shaft; and flows throughra con- 'duit 108 whichconducts it to the usual purification and treating equipment (notshown); In this equipment the valuable by-products are removed and thepurified'gas maythen be'mixed with the gas passingv through the outletpipe 58. By this means substantially all of the valuable by products ofthelcoal may be continuously removed and the coal converted into acoke'or car'- bonized fuel which is very well suited for 1a blue watergas reaction. The gas containing thebyproducts is comparatively small involume, compared with the entire gas output of the producer,

and therefore the by-products may be recovered by treating acomparatively'small amount of gas. .Althoughnthe temperatures used'inthe'blast zone 'for .making gas are comparatively high,

these temperatures are not 'sufliciently high to slag. or clinker'thefuel,-and thereforeacomparatively large amount of the. unburned fuelpasses .down to the bottom of the fuel'columnpi This fuel is principallycoke .or-carbonized fuel and must be quenched to prevent destruction ofthe bottom of theshaft 12. To'thisend .the unburned carbonized fuel andash is supported in the bottom of the shaft upona series of hoppers Y110, Figs. 1, 4 and 5. The hoppers are preferably made of a steelconstruction and. are protected by refractory masonry 1ining. Thehoppers,

seven in number, consist -'of' six peripheral hopv 116, which arespacedfrom, but directly .un- :der the openings. The-platforms 116*arearranged to be given a. reciprocatingmotionfby means of wateroperatedengines 1-18 to'discharge the carbonized fuel from the platforms intosahopper 120 immediately below the hoppers 110.

'To cool the. carbonized fuel passing down'ito the hoppers 110a water orsteam pipe 122 is positionedbelow the hoppers and: has an outlet 124extending into each of the openings 112 .and 114 by which water or steammaybe directed into the carbonized fuel to quench and cool it; The wateror steam introduced intothe hotcarbon- ,ized fuel passes upwardlythrough theifuel 001-.

umn in the form of vapor, thus acting to eifec- .tively cool thecarbonized fuel in its upward passage.

action with the carbonized fuel of "the-fuel column, so that it isutilized'in makinggas in the same way that the steam .enteringthefuel-1column through the preheateris used.

The carbonized fuel discharged from the hoppers 110 to the hopper 120passes th'roughiaw series of outlets 126 on the bottom of. the hopper12(land "-is collected in: a chamber 128 atthe'bottom of'- the shaft.Periodically'a door 130 at the bottom :of the chamber 128- is openedandthe carbonized fuel accumulated thereinmay'be drawn out; At the time thedoor 130'is opened to withdraw carbonized fuel from the chamber 128,doors 132 are moved into position to cover the outlets126xby- V V .7 I

i In other words,;.by preheating the= .steam, air, ;and carb0n,-;,thenitrogen content is'reduce'd from.

meansof operating shafts 134th'atexte'nd tothe outside of; the gasgenerating shaft 12. When the onstrated as follows;

.stantially 6263 B. t; u. may be made.

door 130 is closedthedoors 132 are opened to "permit the carbonized:fuel to pass from the hopper 120 to' the chamber 128 and thus thecarbonized fuel and ashes may be withdrawn from thebottom of theshaftwithout allo'wing gas to escape. To assistin moving the carbon.-

iz'e'd fuel through the hopper 120 a series of pokers: 136 passthroughthe chamber-128 and the hopper 120, by which the carbonized fuel may bebarred J and 'brokenup while it is passing down to the openings 126' ofthe hopper-120: l

a An important feature of the present invention consists in giving ahigh degree of preheat tothe mixture of air and steam being used formaking gas whereby. the inert material from the. coming the steam andairthegas can be made with a lower percentage "of air in proportion tothe amount of steam used, and thus cut down'the amount of inerts in thegas.

.Inthe exothermic reaction between carbon and air' when bothtthe carbonand'the air start'cold,

the following reaction takes place;

If, however; the air-is preheated to 2000f, F. and

the'carbon is preheated to 1500 F. a gain of sub- "In the endothermicreaction between carbon This maybe demand. water vapcr on the basis thatcarbon is cold 'fcigii oecozafzia -imo B. t. u.

'imate1y i125 B..-t.'u. may be made.

If; however, the-steam is preheated to 2000 F. and 1 the carbon isheated to 1500f F.,'a'gain.of approx- 1 l '5 The endothermic reactionbetween carbonand carbon-dioxide, assuming-that both arefcold, is

substantially. as follows; l

o+coiz =zoo tedoa t. u. If, however, the C92 is preheated to 2000-F. and

' the carbon is preheated to 900 Ra gain of'substantially2725'B't. 11.maybe effected: .Assuniv ing that theabove reactions take, place whenthe constituents'are cold, as outlined above, a thermal heat balance maybe obtainedwhen the endothermic reaction between carbon and watervapor-and the carb'onand carbon dioxide constithe analysis of theg'aswould be in percentages By the time the steam'reaches the blast zone itis highlypreheated and enters'into re-.

by volume.

, v 002 252 i-i2{,=22.s N2=52.'0, V Bitiuivalue of gas percubicfoot,='75.5.-

However; whenvassuming thatthe reactions take place, when the steamandair-are heatedto 2000" 'F. and the carbon is heatedto 1500 F.- a}thermal .heatbalance will take place when=39% of the constituents enter:into exothermic reactions, and

61% of the constituents enter into an endotherftutes 45% of thereaction, and the exothermic I V 52 to- 39.7%, the inerts are reducedfrom 77.2 to

66.9% and the calorific values increased from .74'.5 to 108 B. t. u. percubic foot. In the'presentprocess the degree of preheat depends strictlyupon the .nature of the coal which is being treated,-and,

, preferably. will vary from 1200 F. to 2200" F. -By

i of the shaft, a centrally-disposedgas offtake in the shaft with itsinlet adjacentthe'vertical mid- .water. gas.

preheating, a gas having a calorific valueof; from 200-to 225 B. t. u.per cubicfoot may be produced whichhas'most of the advantageous-featuresof The products of combustion of this gas will have a calorific valueranging from.80-- B. t. u. per cubic feeteven when no preheat isimparted to the blast air.

A typical analysis of a gas made by theipresent process is substantiallyas-follows:

In accordance with the character of the coal being treated a gas maybemadewhich willhave a total. amount of inerts of from 45 to 52 per cent.Furthermore by the low temperature carboniz'ation applicant is able togain asubs'tantial'amount in volume of methane produced and also gainsconsiderably in the amount of carbon monoxide is therefore suitable forpractically all industrial heating purposes.

With the process and apparatus outlined above, it will'be seen that themanufacture of gas may be thoroughly controlled, and that the processwill give a very good heat balance because the fuel is introduced andremoved fromthe generator substantially cold, and the residual vheatinthe gas is substantially all removed to the waste'heat boiler. The heatof the gas is. used for generating steam and for superheating the steam.

This case is a division of my copending patent :means for introducing.solid: fuel into .the upper portion of the shaft, means for removingcarbonized'fueland ashes-from the lower portion of the-shaft:.centrallyrthereof, a pair of independentlyapplication Serial No.640,828, filed May 23,1923, for Manufacture of fuel gas, now maturedfasPatent 1,837,226, dated December '22, 1931;

'The preferred form of the inventionnhaving been thusdescribed, what isclaimed as new is:

I claimi I 1. A gas generator comprising'an upright shaft, meansforintroducing solid fuel: to the upper portion of the shaft, means forremoving carbonized fuel and ashes from the lower portion of theishaft,

, a pair of-preheaters, a pair of blast inlets respectively connectingthe. midportion of itheshaft with the respective preheaters, a gas.offtake mounted in the central portionof the. shaft with an inletadjacent the vertical mid-portion of the same, a steam superheatersupportedin the said gas ofi-take, a pair of waste-heatboilers, separatevalve-controlled means adapted to conduct gas from the said gasioff-taketo each of the..:said

waste heat.boilers,-means for conducting away cool gas from each of thesaid boilers, and separate valve-controlled means connecting eachof thesaid boilers with a corresponding preheater.

2. A gas generator comprising an uprightshaft,

means for introducing solid fuel to the upper portion of. the shaft,means for removing carbonized fuel and ashes from the lower .pOrtion ofthe shaft, a blast inlet connected to the mid-portion portion oftheshaft, a peripheral gas-orf-take .connected withr-thetop portion ofthe shaft,:a

waste-heat: boiler, valveecontrolled indirect: heatexchange meansincluding a steam superheater .mountedin the-first-mentionedg-asofftake, and

separate valve-controlled means respectively con- "nectingtheheatexchange'means with the wasteheatboiler and Withthe said blastinlet.

:3. generator comprising an upright: shaft,

l means for introducing solid :fuelto the upper. portion of -the. shaft,means. for'advancing thefuel through the shaft and for removingcarbonized ,fuel and ashes :from the'lowerportion'of the shaft,: a valvecontrolled' blast inletwconnected: t0

the vertical mid-portion. of the shaft,,a' gas offtakeinthecentralportion of the-shaft with its inlet-adjacenttheverticalmid-portion of the shaft, a peripheral gas-ofitake connected.with

the top portion ofxthe shaft, a waste heat boiler,

:indirect heat-exchange means including steamsuperheating.elements-mounted in thefirst-mentioned: gas-ofita'ke, andvalve-controlled passages respectively: connecting the heat-exchangemeans with the wastes-heat boiler and withthesaid blast inlet.

controlled blastzinlets connected with themidportion of thewshaft, a;preheater connectedwith each blast inlet, agas-offta'ke .mountedin thethe'heat exchanger with the respective wasteheat boilers, meansconnecting the said heat-exchanger with. the respective preheaters, andsep- :aratemeansfor respectively introducinggas and I air: forcombustion: into the respective 'preheaters.

- 5..-Agas generator comprising an .upright shaft,

controlled blast. inlets 'c'onnected'with themidportionof theshaft, apreheater connectednwith eachblast inlet, agas-offta'ke' mounted in thecentral portion zofith'e shaft with its inlet adjacent the vertical.mideportion of the shaftand substantially: above. the: elevation of thesaid .blast -inlets, a pair of waste-heat boilers, aheat-exachangeunitmounted in theinterior of the said gas ofita'ke,independent valve-controlled means connecting the heat-exchanger withthe respecitive waste-heat boilers, means. connecting the saidheat-exchanger with the .respective preheaters,

valve-controlled 'means .connecting each wasteheat boiler with acorresponding preheater, and

.means for respectively introducing gasand air for combustionintotherespectiVe preheaters.

:6. In gas generatingsapparatus; an upright gas "generator'shaft havingmeans neariits base for supporting fuelin' a column in the shaft. and.for

advancing: fuel therethrough at a controlled rate, a blastair'inleticonnec'ted with the 'mideportion ofxtheshaft;vertically+spaced axiallyand' peripherally located g'asoiftakesrespectivelydisposed 'atelevations above the saidblastiinlet,the-:said :axiallyvlocated 'gas offtake havingits inletiend adjacent thevertical. mid'eportion. of the: shaft" :4. :Agas generatorcomprisinganuprightshaft, means forrintroducingisolid fuel into; theupper portion of the shaft; means foraremovin'g' carbonizedfuel an'dashes from the. lower portion of the shaft centrally thereof,. a..pairof independentlyand being adapted to withdraw highly heated combustiblegases upwardly from the high temperature zone of a fuel column withinthe shaft while maintaining them out of direct contact with the saidfuel, a fuel inlet in the top of the genthe longitudinal axis thereofand adaptedtoconduct highly heated combustion gases upward axially fromthe high temperature mid-portion of the shaft while maintaining them outof contact with solid fuel, a pair of heat regenerators, valvecontro1ledconnections between the respective regenerators and the verticalmid-portion of the shaft, means in the upper part of the shaft forwithdrawing combustible gases upwardly through the column of coaltherein, and a pair of waste heat boilers, the said jacketed means beingseparately connected with the respective iregener-- ators and with therespective waste heat boilers.

HENRY O. LOEBELL.

